Exams › JEE Advanced › Chemistry
In water, the aluminate species \([Al(H_2O)_6(OH)_4]\) forms, indicating that aluminum's coordination number is 6. What is the nature of this species?
- Highly basic
- Mildly acidic
- Highly acidic
- Mildly basic
Correct answer: Mildly acidic
Solution
The complex contains Al(III), a small and highly charged cation, which strongly polarizes the O–H bonds of coordinated water molecules. This promotes hydrolysis and release of H+ ions, so the species behaves as mildly acidic.
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